docs: def get_image_array(self):
          """Create an array for use in making an image.
  
          Creates a linear stretch of the image and scales it to between `0` and
          `255`. `Null`, `Lis` and `Lrs` pixels are set to `0`. `His` and `Hrs`
          pixels are set to `255`.
  
          Usage::
  
              from pysis import CubeFile
              from PIL import Image
  
              # Read in the image and create the image data
              image = CubeFile.open('test.cub')
              data = image.get_image_array()
  
              # Save the first band to a new file
              Image.fromarray(data[0]).save('test.png')
  
          :returns:
              A uint8 array of pixel values.
          """
          specials_mask = self.specials_mask()
          data = self.data.copy()
  
          data[specials_mask] -= data[specials_mask].min()
          data[specials_mask] *= 255 / data[specials_mask].max()
  
          data[data == self.specials['His']] = 255
          data[data == self.specials['Hrs']] = 255
  
          return data.astype(numpy.uint8)